1. Technical Field
The present invention relates to a light source apparatus and a projector.
2. Related Art
There is a known light source apparatus that irradiates a phosphor layer with excitation light outputted from a laser or any other light source and uses light emitted from the phosphor layer to form illumination light. The light source apparatus is used in a projector including a light modulator, and a technology that meets a need for high luminance has been proposed (see JP-A-2011-128482, for example).
The light source apparatus described in JP-A-2011-128482 includes a first light source apparatus having a first light source that outputs primary excitation light and a phosphor layer that converts the primary excitation light into fluorescence and outputs the fluorescence, a second light source apparatus having a second light source that outputs secondary excitation light, and an excitation light reflection mirror that is disposed on the optical path of the first light source apparatus and has an excitation light reflecting portion and an excitation light transmitting portion. The secondary excitation light passes through the excitation light transmitting portion and impinges on the phosphor layer from the side opposite to the side on which the primary excitation light impinges, and the phosphor layer also converts the secondary excitation light into fluorescence and outputs the fluorescence.
The light source apparatus of the related art described above, however, requires not only the first light source apparatus that outputs primary excitation light but also the second light source that outputs secondary excitation light. Since the light source apparatus of the related art further includes a lens which guides the second excitation light and the excitation light reflection mirror, the number of parts and the size of the entire apparatus undesirably increase. Further, since part of the excitation light reflection mirror, which needs to transmit the secondary excitation light, forms an excitation light transmitting region, part of the excitation light from the first light source is not undesirably used in an effective manner.